Equilibrium hydrate dissociation conditions (vapor + hydrate + liquid water + liquid HCFC141b or cyclopentane) formed from CO2 + water + HCFC141b or cyclopentane are determined using an isochoric method in this work. HCFC141b and cyclopentane are reported to form the structure II hydrates. Phase equilibrium pressures of the experimental systems of CO2 + water + HCFC141b or cyclopentane are all lower than that of CO2 + H2O at any given temperatures. The presence of HCFC141b has more effect on lowering CO2 hydrate equilibrium pressures at lower temperatures than that of cyclopentane, but HCFC141b and cyclopentane have the similar effect on CO2 hydrate equilibrium pressures at higher temperatures.